1. Field
Power driven dental scalers are well known. Of particular interest herein is a dental scaler having vibratable scaling work tool for removing calculus from teeth, which dental scaler utilizes a stream of water to aid in scaling efficiency and in removal of accumulated debris.
2. State of the Art
Of the power driven dental scalers currently available, most common are scalers utilizing a flow of compressed air or a solid-state ultrasonic transducer to cause a scraping type work tool to vibrate.
Typical of the earlier air-driven dental scalers are those of U.S. Pat. No. 3,082,529 and No. 3,444,622 to Mills et al, which scalers utilize an air-driven ball contained in a chmaber. Movement of the ball against the walls of the chamber imparts vibration to the chamber, which vibrations are then transmitted to the scraping tool. A more recent type of air-driven scaler, described in U.S. Pat. No. 3,526,962 to Fuerst, utilizes a rotatable mandrel which has an irregularly-shaped tip engaged with a reciprocable block in which the mandrel tip is received.
It is characteristically a problem of these air driven scalers that much of the vibrational energy generated by the vibrator motor is transferred to the handle portion of the dental scaler rather than to the scraper work tool. Moreover, the modes of vibration of these scalers may change as moving parts of the vibration generating mechanism wear with time.
In U.S. Pat. No. 3,703,037 to Robinson, there is described a dental scaler which utilizes a solid state ultrasonic transducer to provide constant modes of vibration for coupling with particular types of work tools. One disadvantage of the ultrasonic scaler, however, is the cost of the transducer and its fairly sophisticated ultrasonic generator.
A different air-driven dental scaler is disclosed in U.S. Pat. No. Re. 29,687 to Sertich. This dental scaler has very few moving parts as compared to the aforementioned mechanically complicated air-driven scalers and provides efficient transfer of vibrational energy to a scraping-type work tool with relatively little vibration being transferred to the handle portion of the instrument. Moreover, this type of scaler provides uniform modes of constant vibration which may be matched with the vibratory modes of various types of work tools without the need for complicated electronic components.
It has been found that a flow of water over a tooth surface can provide increased scaling efficiency and patient comfort by lubricating the tooth surface and by flushing scaled debris and blood from the surface and area being cleaned. A solid state type dental scaler utilizing a flow of water to improve cleaning efficiency is described in U.S. Pat. No. 4,038,571 to Hellenkamp. One disadvantage of the Hellenkamp device, in addition to that of relatively high cost, is the shock hazard associated with the use of both electrical power and water in a hand-held instrument.
It would be desirable to have a non-electrical, air-driven dental scaler having means for delivering water to the scaler tip. Of particular advantage would be a relatively low-cost air-driven dental scaler having the scaling efficiency advantages of the "Sertich-type" scaler together with the advantage of water flow at the scaler tip to enhance the cleaning action.
A particular problem which occurs frequently in the use of dental instruments utilizing water transport tubes with small bores (such as 0.020 inch or less) is clogging of the tube with sediment or minerals carried in the stream of water. Hence, it would be of benefit for a scaler to have a water supply tube that is easily accessible and quickly replaceable in the event it becomes clogged.
There is need, therefore, for a compact, readily repairable air-driven dental scaler having means incorporated therein for delivering water to a scaling tip.